Accumulation of γ-Linolenic Acid by over-expression of a liverwort Δ-6 Desaturase Gene in Transgenic Rice

Abstract

γ-linolenic acid (C18:3 Δ^6,9,12) is widely used as a dietary supplement and for treatment of various medical conditions. It is a component of fatty acids in several plant species. γ-linolenic acid is synthesized by a Δ-6 fatty acid desaturase using linolenic acid (C18:2 Δ^9,12) as substrate. To enable the production of γ-linolenic acid in conventional cereals, we produced transgenic rice plants that express the transcripts of a liverwort Marchanita polymorpha Δ-6 fatty acid desaturase gene MpDES6 under the control of the maize ubiquitin promoter. The transgenic rice plants had 1-2 copies of the transgenes. The MpDES6 gene over-expressed in the transformants. Analysis of leaf, root and seed lipids from transformed plants demonstrated the accumulation of γ-linolenic acid and octadecatetraenoic acid (C18:4 ^6,9,12,15) .